1. Field of the invention.
The present invention is an improved wrench for removing stud bolts, and more particularly, to the type that cannot be removed with a conventional wrench due to their damaged condition.
2. Description of the Related Art.
For many years the users have been facing different difficulties in removing or unscrewing bolts or the like with hand tools, specially, when they are damaged in place, lost the bolt head and/or the bolt shank is broken. For example, the stud bolts that are used in the twin-wheels of trucks are deteriorated due to the external aggressive environment and the operator spends long time and effort trying to remove broken stud bolts aided by any suitable wrench or stud extractor. Those existing wrenches and extractors are expensive to manufacture, consist of numerous parts, complicate mechanisms and are not easily to manipulate where the space to work around the stud bolt is very restricted. Other stud bolt removers cannot work without the impact of an iron maul. The present invention overcomes the shortcomings found in the existing wrenches.
The closest reference found with characteristics similar to the present invention corresponds to U.S. Pat. No. 2,550,929 entitled Ratcheting Stud Wrench and issued in 1949 to J. Keiser. However, it differs from the invention because the patented stud gripping mechanism includes springs 30 and dogs 20 swinging about pins 23. The present invention discloses a wrench having a simple stud bolt gripping mechanism comprising three main parts: handle, socket assembly and gripping toothed dogs. Also, the present invention discloses removable gripping toothed dogs that can be easily replaced with new ones without the need of replacing the entire wrench, as commonly occurs with the existing stud bolt removers. In view that the cost is considerably minimized, this is one of the main advantages of the present invention.